Identification of novel variants of High Molecular Weight Glutenin Subunits in Indian bread wheat landraces

The High Molecular Weight Glutenin Subunits (HMW GS) in bread wheat landraces were studied using the SDS-PAGE technique. Out of the 32 landraces, 23 were homogeneous while nine showed heterogeneity with respect to the HMW glutenin subunits. Novel variants were observed in HMW GS in four of the landraces. One novel subunit coded by the Glu-Blx locus and two novel subunit pairs at the Glu-D1 locus were identified. A modified system of nomenclature over that of Payne and Lawrence (1983) is suggested for numbering the new subunits. Accordingly, the novel subunits are numbered as 7(1)(Ght-B1x) and 2+12(2); 5(1)+12(2); 5(2)+12(3) and 5(3)+12(3) (Glu-D1x+y) and the allelic designations are given as Ght-B1 bh for 7(1) + 9; Glu-D1bp for 2+12(2). Glu-D1bq for 5(1)+12; Glu-D1br for 5(1)+12(2); GluD1br for 5(2)+12(3) and GluD1bt for 5(3)+12(3).